Finger block for wedge mechanism



Mar. 27, 1923.

1,449,454 0. A. SMITH Y FINGER BLOCK FOR WEDGE MECHANISM Filed Dec. 15,1921 2 sheets-sheet l Mar. 27, 1923.

O. A. SMITH FINGER BLOCK FOR WEDGE MECHANISM Filed Dec. 15, 1921 Z w M m05 car/Z SSW/7% Patented Mar. 27, 19233.

OSCAR A. SMITH, or EAST CLEVELAND, OHIO, Assrenoa 'ro NATIONAL Acmnooir-1 PANY, or CLEVELAND, OHIO, A. oonrona'rron or OHIO. I

FINGER BLOCK FOR WEDGE MECHANISM.

Application filed December 15, 1921. Serial No. 522,512.

To all whom it mag concern:

Be it known that I, OSCAR A. SMITH, a

citizen of the United States, residing at East Cleveland, in the countyof Cuyahoga 5 and State of Ohio, have invented certain new and usefulImprovements in Finger Blocks for l/Vedge Mechanism, of which thefollowing is a specification. a r

This invention relates to finger blocks or finger holding means forwedge mechanism on revolving spindles adapted preferably to operate inconjunction with automatically operative spring chucks or collets, anobject of the invention being to provide im- 16 proved mechanism of thisgeneral character particularly designed and adapted to be used in metalworking machines wherein an improved means is provided for positivelypreventing or resisting the tendency of the an operating fingers tospread through centrifugal force while the spindle is revolving duringoperation.

A further object. of this invention is to provide an improved mechanismof this character which will be more simple and compact in structure,eflicient and effective 1 in operation, and economical to manufacture.

Other objects of this invention will appear in the following descriptionthereof, reference being had to the accompanying drawings forming apart'of this specification, wherein like reference characters indicatecorresponding parts in the several views and wherein Fig. 1 is a sideelevation partly broken away. illustrating my invention; Fig. 2 is aright hand end view thereof; Fig 3is a section taken substantially onlines v83 of Fig. 1 in the direction of the 40 arrow; Fig. 4 is aperspective view illustrating the fingerblock or holder and a fingerpivot screw withdrawn therefrom; Fig 5 is adetail view of a finger; andFig. 6 is a detail view illustrating the various parts of the lungermechanism. H dretofore one of the main disadvantages residing in fingerblock mechanism was occasioned by the fact that upon shifting the wedgemechanism in order to release the fingers, and thereby permit the springchucks or collets or the like to release themselves, the centrifugalforce set up by the revolving spindle often 1 caused the fingers tospread. This spreading of the fingers interfered considerably with theefficiency or effective operation of the spring collet or chuckingmechanism particularly, counteracting an effective opening or releasingof the collet or chuck.

Thus the purpose of the present invention is to do away with thesedisadvantages and particularly eliminate such impediment to the openingor release of the chucking mechanism arising heretofore from centrifugalforce.

Referring to the drawings it will be seen that the usual wedge or coneshaped sleeve 10 is slidably mounted upon the spindle 9 and is adaptedto be shifted in any suitable manner upon the spindle relatively to thefinger block. In the present instance the inadvertent or accidentalfinger holding means or support comprises a finger block 12 adapted tobe screwed onto the spindle9 or otherwise secured thereto, and providedat the rear end thereof withv a pair of diametrically opposed slots 13and 14. Within each slot is pivotally mounted a finger or operatinglever 15, pivoted by means of a pivot screw 17 inserted in suit ableholes 16 tapped in the finger block at right angles to the slots 13 and14:, the pivots 17 adapted to pass through pivot holes 19 in i the pairof fingers or operating levers. It will be noted that each finger 15 isprovided at the rear end with a, thrust portion 20.

adapted to engage the rear end of the usual chucking tube (not shown)and to shift the same for the purpose of'operating the chuck as is wellknown in the art. At the forward end 21 each finger is constructed tocooperate with the tapered portion 11 of the Wedge.

In the rear or extended portion 18 of the finger holding means, asuitable distance away from the rearward face and at a suit able angleto thefinger or lever slots 13 and 14, is bored a pair of two'sectionholes or slots 22 and 23, extending in the same plane I and parallel toeach other. These bores comprise portions or sections of enlarged diameter terminating inportions 21 and 25 of reduced diameter. In theseholes or bores are housed a pair of plungers 26, the headed portionsthereof corresponding substantially ion to the large diameter of holes22 and 23, and.

the stems thereof loosely fitting the small diameters 24 and 25 of theholes. In rear of and resting against the head of each pin 26 is housedin each hole a compression spring 27 the same being held firmly inposition by means of a pair of adjusting screws 28 cooperating with thethreaded portions 29 of the respective holes or slots. By adjustingthese screws 28 it will be readily seen that the tenion of springs27 maybeadjusted or varied as desired, thereby varying the pressure exerted bythe plungers upon the operating fingers or levers.

Into the rearward face and preferably at a suitable distance above thepivoting holes '19 of the fingers, are milled stations or recesses 30.These recesses it will be noted form seats having the walls 31 thereofat right angles to the direction of operation of the plungers 26, andthe walls 32 thereof in substantial parallel relation thereto. As aresult the milled stations or seats are angularly formed to correspondtothe angular position of the plungers, and the plungers 25 projectthrough the slots 13 and 14 into "these stations or seats under constantpressure from the compression springs 27.

In operation it will be readily seen that when the automatic springcollet or chuck releases as a result of the shifting-of the wedge 10,soas to travel away from the finger block 12, the fingers 15 collapse asindicated in dotted lines in Fig. 1 by virtue of the outward lateralforce exerted by the plungers in rear of pivots 17 upon the operatingfingers. The fingers however will be positively held in this positionagainst the centrifugal force of the revolving spindle due to the factthat the spring controlled plungers 26 exert continuous pressure uponthe ends of thefingers thereby overcoming and'counter-acting thecentrifugal force. This resistance to the spreading of the fingersjisincreaSed due to the fact that the fingers'have'a positive frictionalengagement with the ends of the plungers. WVhen the inner ends areforced inwardly the walls or faces 31 slide over the ends of theplungers, which frictional contact together with the resistance of thesprings forms a Very effective and positive resistance to the spreadingof the fingers.

It will be further scen'that I have provided not only a mechanism forefiiciently controlling the position of the operating "fingers but Ihave also provided a compact structure wherein the finger controllingmechanism is mounted entirely within the finger block thereby resultingnot only in more directness of operation but also in considerablesimplification and economy in construction.

Although I have described my invention inits preferred form, it is tobeunderstood that I do not limit myself to the construction herein shownand described except in so far as defined in the claims and embracedwithin the scope thereof.

I claim as my invention:

1. The combination of a spindle, a finger holder carried thereby, achuck operating finger pivotally carried bysaidfinger holder, meanscarried by the spindle 'for swinging said finger in one direction, andspring pressed means engaging the finger at the rear of its pivotalpoint for swinging the finger inthe opposite direction and operative ina direction transverse to the plane of movement of said finger.

2. The combination of a spindle, a finger holder carried thereby, achuck operating finger pivotally carried by saidfinger holder, meanscarried by the spindle for swinging said finger in one direction, andspring pressed plunger means for swinging the finger in the oppositedirection and operative in a direction transverse to the plane ofmovement of said finger. i

8. The combination of supporting means, a plurality of chuck operatingfingers pivotally carried thereby, means for engaging the opposed facesof said fingers for swinging tl e fingers in one direction to spreadthem, and means positioned to have a movement transversely to the planeof swing of said fingers for frictionally and resiliently resisting suchmovement. i

4. The combination of supporting means, a plurality of chuck operatingfingers pivotally carried thereby, means for'engaging the opposed facesof said fingers for swinging the fingers in one direction to spreadthem, and'means positioned to have a movementtransversely to the planeof swing of 'said fingers for frictionally and resiliently springpressed plungers'.

'5. The combination of a spindle, a finger block adapted to be connectedthereto, chuck operating fingers pivotally carried bysaid finger block,and a pair of means 'coacting with said fingers for swinging the same,said means being operative in different directions and having the axisthereof extending outside the axis ofthe spindle and in position toengage; the finger at the rear of its pivotal point, thereby to exert apushing action thereon.

6. The combination of aspindle, a finger block adapted to be connectedthereto, a chuck operating finger pivotally carried by said fingerblock, and meanscoacting with 'said finger for swinging thesame, said"adjacent to one end thereof to said holding means, and means forswinging the finger and having one end engaging said finger in rear ofits pivot and the other end extend through said finger holding means andterminating adjacent to the exterior thereof.

8. The combination of a spindle, a finger holder carried thereby andhaving a pair of opposed slots, chuck operating fingers pivoted in saidslots, and a pair of means coacting with said fingers and operative indifferent directions and located to exert a pushing action on andthereby swing said fingers, each of said means having the axis thereofextending outside the axis of the spindle.

9. The combination of a finger holder having a pair of opposed slots,chuck operating fingers pivoted in said slots, and means for swingingsaid fingers, said means extending through the finger holder from theoutside thereof into engagement with said fingers.

10. The combination oi a spindle, finger supporting means mountedthereon, a chuck operating finger pivotally carried by said supportingmeans, and spring pressed means engaging the side of said finger forswinging the same.

11. The combination of a finger holder having a. pair of opposed slots,chuck operating fingers in said slots, and adjustable.

spring controlled means for swinging said fingers, said means extendingthrough the finger holder from the outside thereof into engagement withsaid fin 'ers.

12. The combination of a rotary spindle, finger supporting means carriedthereby, a chuck operating finger pivoted to said supporting means andswingable in the plane of the axis of said spindle, and an adjustablespring actuated plunger engaging the side face of said plunger forswinging the same.

13. The combination of a finger holder having a slot, a chuck opera-tingfinger pivoted in said slot and having a recess in its side and a springcontrolled plunger carried by said holder and projecting into saidrecess.

14. The combination of a finger holder, a

thereby and having at a side face thereof a plunger receiving seat and aplunger engaging said seat.

15. The combination of a finger holder, a chuck operating fingerpivotally carried thereby and provided with a recess having angularwalls, and a plunger projecting into said recess, said holder having arecess open at both ends for receiving said plunger.

16. The combination of a finger holder, a chuck operating finger pivotedthereto, and resilient means extending substantially through said holderfor controlling the same.

17. A finger holder for chuck operating fingers having an axialslot andan angular hole communicating therewith and open at both ends.

18. The combination of supporting means, a plurality of fingerspivotally carried thereby, means for swinging said fingers in onedirection, meansfor resisting such movement and comprising a plungerdirectly engaging each ofsaid fingers at an angle to the sides thereof,and resilient means cooperating with said plunger.

. 19. The combination of supporting means, a plurality of pivotedfingers carried thereby, wedglng means for engaging the opposed faces ofthe fingers at one end thereof thereby to spread. said ends, and meansfor engaging the fingers at the opposite ends thereof and located at anangle to the sides of the fingers for spreading the opposite ends ofsaid fingers,

20. The combination of a spindle, finger supporting means mountedthereon, a chuck operating finger pivotally supported intermediate itslength on said supporting means, means for engaging the finger at oneside of its pivotal point for operatingthe finger in one direction, andmeans for engaging the finger at the other side of its pivotalpoint andlocated at an angle to the side of the finger for operating the fingerin the opposite direction.

Signed at Cleveland, Ohio, this 12th day or December, 1921.

' OSCAR A. SMITH.

